Method of using bilumen peripheral venous catheter with adapter

ABSTRACT

Bilumen catheters of the present invention have tow lumens to supply two non-miscible liquids simultaneously and a method for their use. The two lumens are enclosed within a single catheter and have different cross-sections, the lumen of larger cross-section being adapted to infuse or remove higher viscosity fluids, such as blood, and the lumen of smaller cross-section designed to infuse or remove lower viscosity fluids. Catheters of this invention are more narrow than prior art catheters so that they need not be employed in the vicinity of the heart or other vital organs and may be used in peripheral portions of a patient&#39;s body, such as the patient&#39;s limbs. This invention reduces the likelihood of blood clots, dysarythmias and infection. They do not need highly trained individuals, such as doctors, for injection purposes, but may be used by any paramedic or nurse in an emergency. This invention also comprises an adapter of special construction that facilitates connecting said lumens simultaneously to sources of different fluids for simultaneous infusion thereof into a peripheral cavity of a patient.

This application is a division of Ser. No. 06/906,138, filed Sept. 11,1986 for Bilumen Peripheral Venous Catheter with Adapter now U.S. Pat.No. 4,776,841.

BACKGROUND OF THE INVENTION

I. Field of the Invention

This invention relates to surgical instruments for introducing fluidsinto a cavity of a body. It has special utility in the simultaneousintroduction of non-compatible fluids, particularly those that arenon-miscible and those having different viscosities.

II. Description of the Related Art

A catheter is a tubular medical device that is inserted into vessels orbody cavities to permit the injection or removal of fluids or substancesor to maintain open a passageway within a body of a patient. The term"patient" is used to include animals as well as humans. In the past,catheters have been provided with one or more lumens, which areelongated tubes that are incorporated within the body of a catheter andextend in the form of a tube or a hollow needle.

One type of catheter used in the prior art is known as a central venouscatheter. This type of catheter is generally inserted into thesubclavien vein or the external jugular vein, all located within closeproximity of a vital organ such as the chest and heart. Usually thecentral venous catheter is a long cylindrical tube approximately 20 to30 centimeters (8 to 12 inches) long and has a diameter of approximately0.3 centimeters (1/8 inch). One type of central venous catheter is knownas a tri-lumen central venous pressure line. Such a pressure linecontains 3 lumens, each of which extends from an extended diaphragm to atrifurcation member where the 3 lumens are held together. Fluid of aunique characteristic desired to be imparted or injected into anindividual patient is applied using a syringe to inject a differentunique fluid into each of the 3 diaphragms. The 3 different fluids entera respective lumen for further movement of the respective fluids towardstheir points of discharge into the body of the patient. Each lumen has adischarge point at different distances from the trifurcation point. Thelumen that discharges fluid into the patient's body at the closest pointto the trifurcation point is called "the proximal discharge point", thelumen having a middle discharge opening is termed "the medial dischargepoint" and the lumen whose discharge point is at the greatest distancefrom the trifurcation point is termed "the distal discharge point".

In prior art devices, the individual lumens had to be of sufficientlylarge cross-section to provide injection of 3 different fluids at 3different spaced positions within the body of the patient. It wasbelieved necessary to provide such injections in the vicinity of thelarge blood vessels near the heart and other vital organs of thepatient. Such proximity to the vital organs rendered the insertion ofcatheters a dangerous job, which made it necessary that a highly trainedand highly skilled person, such as a doctor, had to perform theinsertion of the catheter.

Double current catheters suitable for removing blood from a fistula orvein for processing in a dialysis machine and returning the processedblood back to the fistula or vein is disclosed in U.S. Pat. No.4,134,402 to Mahurkar. Another double lumen catheter provided withadditional features to promote insertion and to perform a dilatorfunction is disclosed in U.S. Pat. No. 4,568,329 to Mahurkar. Thepatents to Mahurkar disclose double lumen continuous flow hemodialysisneedles and cannulae having contiguous lumens of different lengthsformed by dividing a unitary straight tube with an internal longitudinalseptum. The shorter lumen acts as a blood intake lumen and the longerlumen acts as a blood return lumen. In the Mahurkar patents, thecatheters are divided into semi-circular lumens of equal cross-sectionextending side by side for a major portion of the length of thecatheter. In only a short portion at the distal end of the catheter dothe lumens have different cross-sections.

Numerous other United States patents disclose double current cathetersfor hemodialysis that evidence a long felt need for a small,functionally efficient catheter, having a minimum of insertion traumaand potential for clotting. U.S. Pat. No. 4,096,860 to McLaughlindiscloses a coaxial hemodialysis catheter said to allow a stepenlargement of the opening of a blood vessel to avoid its tearing andrupture along its side walls. A simultaneous flow device incorporates ahub with an extension conduit and a valve to receive a needletherethrough. The extension conduit is sufficiently large to allow theneedle to pass therethrough adjacent the interior side walls with anattendant extension thereof from its opening. The needle with theextension conduit is adapted for combined insertion within a bloodvessel, after which it can withdrawn while the valve prevents thebackflow of blood through the axial passage of the hub. A coaxial flowdevice can then be inserted within the hub conduit.

U.S. Pat. No. 4,099,528 to Sorenson et al discloses a coaxial doublelumen cannula mounted upon a hub and having a central stylet needle topenetrate a patient's vein and which is retractable after penetration.This patented technique is a standard procedure for inserting cathetersand is commonly termed the "over the needle" tecchnique.

U.S. Pat. No. 4,203,436 to Grimsrud discloses a hollow hypodermic needlewith a divider to provide a first channel to remove blood for treatmentfrom a punctured blood vessel and a second channel to return the treatedblood to the blood vessel.

U.S. Pat. No. 4,385,631 to Uthmann discloses a hemodialysis catheter topuncture blood vessels. The Uthmann device includes a section insertablethrough a puncture opening into a blood vessel and a hose line followingthereafter.

U.S. Pat. No. 4,403,983 to Edelman et al discloses a dual lumen cannulain the form of a tube divided longitudinally throughout essentially itsentire length by a septum to create two parallel lumens at equalcross-section, one for withdrawing blood from the subclavian vein forextra corporeal processing and the other to return the treated bloodback to the subclavian vein in the area of blood withdrawal.

U.S. Pat. No. 4,180,068 to Jacobson et al discloses a double currenthemodialysis catheter comprising a primary tube and an internal dividerwhich also functions as a trocar and valve. The primary tube has a sideopening to receive blood and a central opening at the distal end of theprimary tube. The internal divider includes a cutting end whichprotrudes from the distal opening when the divider is longitudinallymoved to an insert position. In the insert position, blood flow isblocked.

U.S. Design Pat. No. 272,651 to Mahurkar discloses a double lumencatheter having an outlet lumen which has an opening at the tip of thecatheter and a shorter inlet lumen which terminates in a bevelsubstantially displaced from the tip of the catheter.

None of the patents described provide a catheter having a cross-sectionsufficiently small to encompass a plurality of small cross-sectionlumens which are capable of insertion into a peripheral portion of apatient's body such as the arm or leg of a patient so that differentfluids which are non-miscible with one another can be applied in spacedrelation within the patient's body using peripheral venous catheters,while maintaining integrity and independence of each of a plurality ofinjected fluids or medications being simultaneously applied to thepatient.

SUMMARY OF THE INVENTION

The present invention makes it unnecessary to insert a catheter in thevicinity of a dangerous part of a patient's body, namely the vicinity ofthe heart and other critical organs. The present invention providescatheters that enclose a primary lumen of such small cross-section thatit may be inserted into a patient's body in a peripheral, non-criticalportion thereof, such as an arm or a leg, simultaneously with theapplication of another material of lesser viscosity which is appliedthrough a secondary lumen.

The present invention divides a catheter into lumens of differentcross-sections. The primary lumen has a relatively large cross-sectionthroughout its length sufficient to permit the application or injectionof high viscosity fluids, whereas the secondary lumen enclosed withinthe catheter has a smaller cross-section and a more proximal openingthrough which low viscosity fluids can be applied. The ratio ofcross-sections of said primary and secondary lumens remains essentiallyconstant from the hub of the catheter to the proximal opening at thedistal end of the secondary lumen.

Prior art dual lumen catheters that infuse and remove blood require across-section of catheter that is at least double the 18 gauge lumensrequired for the input and removal of blood. The present invention,which flows blood and a less viscous fluid in adjacent lumenssimultaneously, requires only the blood supplying lumen have an 18gauge, the other lumen for supplying the less viscous fluid can be assmall as 26 gauge and still pass non-viscous fluids. Therefore, thecross-section of the present invention type of catheter need be onlyslightly more than one half of the required cross-section of prior artdual flow catheters. This feature enables the catheter of the presentinvention to be inserted into smaller blood vessels than is possiblewith prior art dual flow catheters, and causes considerably lessdiscomfort to insert than prior art catheters.

Another benefit of the present invention is that it enables people whodo not have the training and experience of physicians or surgeons toinsert the catheter of the present invention without danger to thepatient, because the smaller diameter bilumen catheters of the presentinvention may be inserted into peripheral portions of the body such as apatient's arm or leg rather than in the vicinity of a vital organ and,therefore, the smaller diameter bilumen catheters of the presentinvention are remote from the vicinity of said vital organ. As aconsequence, the smaller diameter bilumen catheters of the presentinvention need not await the arrival of a highly trained doctor toinsert said present invention catheters safely in case of an emergency.Instead, any paramedic or nurse may insert a catheter conforming to thepresent invention into a peripheral blood vessel even in the absence ofa doctor in case of emergency and be secure in the knowledge that thecatheter so inserted is remote from the vicinity of a vital organ.Therefore, the catheters of the present invention do not represent asmuch danger to the patient as prior art bilumen catheters, whose largercross-sections limit their infusion into large diameter blood vesselslocated near vital organs, such as the heart.

Still another feature of the present invention is the inclusion offlexible extension wings which wrap around the wrist or ankle or limb ofthe patient and allows the catheter to be taped in place in a locationspaced from the catheter needle. In a preferred embodiment, the wingsextend transversely from a hub at the proximal end of the catheter inopposite directions for securement to the wrist, ankle or limb from thatoccupied by the hub. This feature reduces the possibility ofcontaminating the needle of the catheter and causing infection thatwould be harmful to the patient.

The present invention is also provided with flexible securing clipsespecially constructed and arranged to enable the catheter to be securedto an adapter quickly and to enable the adapter to be released from thecatheter quickly, easily and cleanly. In a preferred embodiment of thisinvention, the flexible securing clips extend in a proximal directionfrom the hub to be secured to an adapter, whose purpose will bedescribed.

The present invention also comprises an adapter of novel constructionwhich cooperates with the hub constructed and arranged in a specialmanner to facilitate the simultaneous connection of individual, discretesupply tubes to corresponding lumens of a multilumen catheter or to asingle lumen catheter and which also makes possible the readydisconnection of said catheter from said supply tubes.

Finally, the opening at the distal end of the secondary lumen thatextends only part of the length of the catheter is both bevelled andslanted relative to the elongated axis of the catheter. This featureallows the catheter to be inserted easily into a vein of an arm or legof a patient. In the prior art, proximal and medial openings ofcatheters provided with a multiplicity of lumens were only bevelled, andnot slanted.

The aforesaid benefits of the present invention will be betterunderstood in the light of a description of preferred embodiments thatfollow.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings that form part of the description of the presentinvention,

FIG. 1 is a longitudinal view of a bilumen peripheral venous catheterconforming to one embodiment of the present invention;

FIG. 2 is a longitudinal view of one type of adapter provided with abifurcated distal end that engages the proximal end of a hub at theproximal end of the catheter of FIG. 1;

FIG. 3 is a view similar to that of FIG. 1 and FIG. 2, showing analternate construction of catheter and hub;

FIG. 4 is a cross-sectional view along the line 4--4 of FIG. 1;

FIG. 5 is a cross-sectional view along line 5--5 of FIG. 1;

FIG. 6 is a cross-sectional view along line 6--6 of FIG. 1 or FIG. 3;

FIG. 7 is a cross-sectional view along line 7--7 of FIG. 1 or FIG. 3;

FIG. 8 is a cross-sectional view along line 8--8 of FIG. 1 or FIG. 3;

FIG. 9 is a cross-sectional view along line 9--9 of FIG. 1 or FIG. 3;

FIG. 10 is an end view along line 10--10 of FIG. 1 or FIG. 3;

FIG. 11 is a sectional view along line 11--11 of FIG. 2;

FIG. 12 is an enlargement of circular area 12 at the distal end portionof one portion of one of the bifurcated members of the adapter of FIG.2; and

FIG. 13 is an enlarged view of the left-hand portion of FIG. 3.

Referring now to FIGS. 1, 2 and 4 to 10, a preferred embodiment of thepresent invention is disclosed. These drawings show a dual inflow doublelumen catheter 20 conforming to the present invention and an adapter 40of special construction. The catheter is of elongated constructioncontaining a cylindrical shaped proximal portion 31, a medial portion32, which, in turn, merges into a distal portion 33 of narrowfrustoconical shape. Catheter 20 contains a primary lumen 21 preferablyof 18 gauge side by side with a secondary lumen 22 preferably of 26gauge. Medial portion 32 comprises a proximal opening 23 that has aninward bevel 24 merging into an outwardly slanted portion 25. Opening 23extends through the wall of the catheter 20 to provide a discharge pointfor the secondary lumen 22. The primary lumen 21 extends to the distalopening 26 at the distal end of the catheter 20. The outer wall of thecatheter 20 is of cylindrical shape throughout the cylindrical proximalportion 31 and then is apertured in the medial portion 32, which mergesinto the distal portion 33.

A hub 27 having an open end forming a proximal opening of circularcross-section (See FIG. 4) beyond the proximal end of the cylindricalproximal portion 31 of the catheter 20 extends axially from the proximalend of catheter 20. The interior of the hub 27 is provided with a thickdivider wall portion 28 extending axially longitudinally anddiametrically transversely merging into a veering wall portion 29 at thedistal end of hub 27 to divide the hub into chambers. Veering wallportion 29 nxtends into a divider wall 30 that divides substantially theentire length of the catheter into the lumens 21 and 22 of differentcross-section, preferably conforming to 18 gauge and 26 gauge,respectvely, as shown in section in FIGS. 5, 6 and 7. Within hub 27,divider wall portion 28 forms a septum that separates hub 27 intochamber portions that are semi-circular and of equal diameter at theportion of hub 27 that intersects the plane of FIG. 5. Veering wallportion 29 veers obliquely and changes shape gradually from a straightwall portion 28, shown in cross-section in FIG. 5 to the arcuatelyshaped divider wall portion 30 of FIGS. 6 and 7.

FIG. 2, 11 and 12 show a bifurcated adapter 40 which is provided with acentral recess 41 that receives the divider wall portion 28 when thebifurcated adapter 40 is inserted into the hub 27. An annular ring 42encircles recess 41 at the distal end of the adapter 40. Eachbifurcation of adapter 40 has an oblique distal wall 43. Adapter 40 hasa flat proximal end wall 44. Discrete passages 45 and 46 through adapter40 of different cross-sections, extend through adapter 40. Each discretepassage 45 or 46 flanks the central recess 41. The distal end walls 43of the bifurcations that flank recess 41 are oblique. Passages 45 and 46extend from their proximal ends to a pair of tubes 48 that terminate indetachable diaphragms 49. The latter are constructed for coupling anddecoupling with a pair of adapters 149 (see FIG. 2). Adapters 149 areprovided at the distal ends of fluid supply means (FIG. 2) constructedand arranged to connect tubes 48 via detachable diaphragms 49 andadapters 149 to first and second fluid storage means (not shown) forstoring fluids of different viscosities, such as relatively highviscosity blood and a relatively low viscosity nutrient. Thus, thefluids are delivered to lumens 21 and 22 for parallel discrete flowstherethrough in the same direction. A viscous liquid such as blood isinjected by a needle through one of the diaphragms 49 for flow alongtube 48 through the passage 46 of bifurcated adapter 40 and through oneof the chambers of hub 27 through primary lumen 21 for discharge throughdistal end opening 26 into the cavity of a patient. Simultaneously, alow viscosity fluid can be injected from secondary lumen 22, which is ofsmaller cross-sectional area than the primary lumen 21 through the otherdiaphragm 49, the other tube 48, passage 45 and the other chamber of hub27. Having the distal end walls 43 of adapter 40 oblique facilitatesalignment of passages 45 and 46 with lumens 21 and 22 when centralrecess 41 engages wall portion 28.

The hub has attached thereto a pair of transversely extending flexibleelongated extension wings 50 and 51 which are adapted to flex to conformto a peripheral limb of the patient and to extend around said limb. Thisfeature allows catheter 20 to be fixed in position relative to thepatient's limb by taping the extension wings 50 and 51 to said limb inspaced relation to the location where the needle of the catheter entersthrough the skin of the patient. The separation of the area ofattachment from the point where the needle of the catheter penetratesinto the patient's body minimizes contamination of the infusion site.

In addition, flexible securing clips 53 and 54 (FIG. 1) extendproximally from the proximal end of the bifurcated hub 27 and areprovided with inturned ends 55 and 56. The securing clips 53 and 54 andtheir attached inturned ends 55 and 56 are flexible. The adapter 40 hasan oblique outer wall 57 which diverges in the proximal direction. Thisdivergence forces the flexible securing clips 53 and 54 apart as thebifurcated adapter 40 is inserted into the space flanking the dividerwall portion 28 of hub 27. The inturned ends 55 and 56 snap over theproximal flat wall 44 of the annular ring 42 when adapter 40 is fullyinserted in hub 27. When it is desired to disconnect the adapter 40 fromthe hub 27, an outer pull of the adapter 40 causes the end portions 55and 56 to separate readily from one another as the flexible securingclips 53 and 54 permit easy removal of the adapter 40.

It is noted that the outer wall of catheter 20 in the vicinity of theproximal opening 23 at the end of the secondary lumen 22 is bothinwardly bevelled at 24 and outwardly slanted at 25 in the distaldirection toward the portion of the catheter that forms narrowconically-shaped end portion 33, merging from a cylindrically shapedproximal portion 31 along the major portion of the length of thecatheter 20. The fact that the lumen opening 23 is both bevelled andslanted relative to the length of the catheter allows easier insertionand removal of the catheter into a blood vessel of a patient when thecatheter is of the bilumen type that simultaneously infuses or removestwo different, non-compatible fluids to or from a single body cavity.

FIG. 3 shows a modified embodiment of this invention in which a modifiedadapter 140 has passages 45 and 46 extending its full length withpassage 45 widening to conform to the wider cross-section of primarylumen 21 and passage 46 narrowing to conform to the narrowercross-section of secondary lumen 22 at the distal end of modifiedadapter 140. Thus, non-miscible fluids supplied separately through tubes48 and passages 45 and 46 to primary lumen 21 and secondary lumen 22 areimparted simultaneously and independently in parallel paths in the samedirection and are kept from mixing until both liquids enter the body ofa patient undergoing treatment.

It is understood that while the present invention shows a bifurcatedadapter 40 connecting two separated passages 45 and 46 to two separatelumens 21 and 22, the number of separate passages and correspondingnumber of lumens may be increased or decreased without departing fromthe gist of the present invention. Also, if two or more miscible liquidsare supplied through separate passages, the passages may merge withinthe distal end portion of the adapter to feed a mixture of said miscibleliquids before said mixture reaches or at the time said miscible liquidsmixture reaches the proximal end of said catheter without departing fromthe gist of this invention as it pertains to either embodiment ofadapter shown in FIG. 2 or FIG. 3. In FIG. 13, the distal end of anadapter 240 forms a friction fit with a catheter 120.

The present invention is used to simultaneously apply a relatively thin,free flowing liquid, such as a medicinal solution, through a lumenhaving a relatively small cross-section and terminating at a proximalopening that is both bevelled and slanted in cooperation with a primarylumen of larger cross-section not exceeding 18 gauge for infusing ahigher viscosity liquid, such as blood, that extends the full length ofthe catheter and permits the insertion of a catheter end portion havinga relatively narrow cross-section which is all that is needed forinsertion into peripheral portions of the body, such as the limbs. Thebilumen peripheral venous catheters of this invention are also useful insimultaneously infusing different fluids that are non-miscible eventhough their viscosities are equal or almost equal.

According to the provisions of the patent statutes, the preferredconstruction and mode of operation of the present invention has beenexplained and what is now considered to be its best embodiments havebeen illustrated and described. However, it should be understood that,within the scope of the claimed subject matter that follows, theinvention may be practiced otherwise than as specifically illustratedand described.

What is claimed is:
 1. A method of simultaneously injecting twonon-compatible fluids into a peripheral portion of the body of a patientconsisting essentially of inserting a bilumen peripheral venous catheterinto said peripheral portion of said body of said patient, said catheterhaving two lumens of different cross-section within a peripheral wall ofsaid catheter, applying a flow of one of said fluids to one of saidlumens having a relatively small cross-section for delivery into saidbody at a proximal opening along the wall of said catheter andsimultaneously applying a flow of the other of said fluids to the otherof said lumens having a relatively large cross-section not exceeding 18gauge for delivery into said body at a distal opening at the end of saidcatheter.
 2. A method as set forth in claim 1, wherein said fluids havedifferent viscosities and said higher viscosity fluid is caused to flowthrough said lumen having a relatively large cross-section.
 3. A methodas set forth in claim 2, wherein said fluid of relatively high viscosityis blood.
 4. A method as set forth in claim 2, wherein said fluid ofrelatively less viscosity is delivered through an opening in a medialportion of the outer wall of said catheter that is bevelled and slantedrelative to the longitudinal axis of said catheter.
 5. A method ofsimultaneously supplying fluids of different viscosity to differentlumens of different crosssection carried by a common catheter consistingessentially of supplying one of said fluids having relatively highviscosity to a first supply tube of relatively large cross-section andsimultaneously supplying another of said fluids having relatively lowviscosity to a second supply tube of relatively small cross-section andsimultaneously transferring said relatively high viscosity fluid to alumen of relatively large cross-section not exceeding 18 gauge whiletransferring said relatively low viscosity fluid to a lumen ofrelatively small cross-section.
 6. A method as set forth in claim 5,further including injecting said low viscosity fluid from saidrelatively small cross-section lumen to the body of a patient whiletransferring said high viscosity fluid from said relatively largediameter lumen to said body.
 7. A method as set forth in claim 6,further including simultaneously transferring said high viscosity fluidto said body via a distal opening in the wall of said common catheterwhile transferring said low viscosity fluid to said body through aproximal opening of said common catheter.
 8. A method as set forth inclaim 7, wherein said high viscosity fluid transferred is blood.
 9. Amethod as set forth in claim 6, further including simultaneouslytransferring said relatively high viscosity fluid from said first supplytube to said lumen of relatively large cross-section and said relativelylow viscosity fluid from said second supply tube to said lumen ofrelatively small cross-section through an adapter having passagescommunicating with the distal ends of said first supply tube and saidsecond supply tube and a hub communicating with the proximal ends ofsaid lumens by using an adapter readily connected to and disconnectedfrom said hub, said adapter having an oblique outer wall, a flatproximal end wall and an axially extending recess, and said hub having apair of flexible clips extending in a proximal direction from said huband having inturned ends at the proximal ends of said clips and adivider wall adapted to be received by said axially extending recess andconnecting said adapter to said hub by inserting said divider wall intosaid axially extending a recess so that said flexible clips are forcedto separate along said oblique outer wall until said inturned endsengage said flat proximal end wall.
 10. The method as set forth in claim9, further comprising inserting the bilumen catheter into the patient ata location remote from the vicinity of a vital organ of said patient.11. The method as set forth in claim 6, further comprising inserting thebilumen catheter into the patient at a location remote from the vicinityof a vital organ of said patient.